In my senior year at Purdue University, I had the opportunity to conduct microfabrication in the cleanroom at Birck Nanotechnology Center at Purdue. This laboratory course—ECE 557 Integrated Circuit/MEMS Fabrication Lab—taught by Professor David Janes is intended to be for graduate students but he accepted me because of my motivation and interest in micromanufacturing.
After learning and practicing in the cleanroom performing wafer cleaning, photolithography, mask patterning, wet etching, and lift-off for 3 months, I was able to fabricate my own Mirco-Electro-Mechanical Systems switch chips on a 8"x8" silicon wafer.
I had to write my expected pull-down voltages for 90 devices. I did not want to calculate all by hand so I wrote a simple Matlab script with the lengths and widths as vectors to output all 90 values.
After fabrication, I performed electrical characterization where I found out that they did not work. After spending extra hours in the cleanroom with the microscope and re-reading my lab notebook helped me figured out that repeated wet etching caused the structure to be imbalanced and the cantilever beam to be misplaced.